Delivery and retrieval systems for collapsible/expandable prosthetic heart valves

ABSTRACT

A system for delivering a collapsible and re-expandable prosthetic heart valve into a patient includes a valve support structure ( 140 ) around which the valve ( 10 ) is disposed in a collapsed condition. A sheath structure ( 110 ) surrounds the collapsed valve, but can be moved relative to the valve to uncover it for expansion at the desired implant site in the patient. The sheath structure may be variously mounted and moved to deploy the valve in various ways. For example, the sheath structure may include multiple parts, each of which can be moved separately to separately deploy various parts of the valve. The apparatus may have other aspects, such as the ability to reverse deployment of the valve, the ability to pass other instrumentation through the valve delivery apparatus, the ability to be smoothly withdrawn from the patient after deployment of the valve, etc.

This application claims the benefit of U.S. provisional patentapplication No. 61/011,393, filed Jan. 16, 2008, which is herebyincorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

This invention relates to prosthetic heart valves. More particularly,the invention relates to prosthetic heart valves that can be collapsedto a relatively small circumferential size for delivery into a patient'sbody with reduced invasiveness to the patient, and which can then bere-expanded to operating size at the intended implant site in thepatient. Still more particularly, the invention relates to methods andapparatus for delivering a valve of the type described above into apatient and re-expanding the valve at the implant site. Another possibleaspect of the invention relates to methods and apparatus forrepositioning the valve in the patient and/or for retrieving the valvefrom the patient if desired.

SUMMARY OF THE INVENTION

In accordance with certain possible aspects of the invention, apparatusfor delivering a collapsible and re-expandable prosthetic heart valve toan implant site in a patient may include a valve support structurearound which the valve is disposed in a collapsed condition. A sheathstructure may surround the valve on the valve support structure. Theapparatus may still further include means for moving the sheathstructure relative to the valve support structure to uncover the valvefor expansion at the implant site. The valve may have first and secondsurface portions that face in respective opposite first and seconddirections along an axis around which the valve is disposed on the valvesupport structure, and the valve support structure may have third andfourth surface portions that respectively face in the second and firstdirections. The first and third surface portions may be positionedadjacent to and facing one another, and the second and fourth surfaceportions may be positioned adjacent to and facing one another tosubstantially prevent relative movement of the valve and the valvesupport structure along said axis while the valve is disposed around thevalve support structure in the collapsed condition.

In accordance with a further possible aspect of the invention, thesheath structure may include a first sheath part that covers a firstaxial end part of the valve in the collapsed condition, and a secondsheath part that covers a second axial end part of the valve in thecollapsed condition. In such a case, the means for moving may makepossible movement of one of the sheath parts relative to the othersheath part. Further in such a case, the means for moving may includefirst means for moving the first sheath part in a first direction thatis away from the second axial end part of the valve; and the means formoving may further include second means for moving the second sheathpart in a second direction that is away from the first axial end part ofthe valve. If provided, the first and second sheath parts may partlyoverlap one another.

In accordance with another possible aspect of the invention, the valvesupport structure may be configured to substantially prevent the valvefrom rotating about the valve support structure.

In accordance with still another possible aspect of the invention, theapparatus may further include means for drawing a portion of the valvethat has been uncovered by the sheath structure radially inwardly towardthe valve support structure.

In accordance with yet another possible aspect of the invention, themeans for moving may additionally allow the sheath structure to be againmoved relative to the valve support structure after expansion of thevalve so that the sheath structure covers the valve support structure.

In accordance with still another possible aspect of the invention, thevalve support structure may define a passageway that extends from afirst location that is proximal of the valve to a second location thatis distal of the valve, with the first location being closer to anoperator of the apparatus than the second location.

In accordance with yet another possible aspect of the invention, thevalve support structure may define a passageway for fluid communicationfrom a location that is proximal of the valve to the valve, with saidlocation being closer to an operator of the apparatus than the valve.

In a case in which the valve has first and second axial end parts, asmentioned above, one of the axial end parts may include valve leaflets,and the other axial end part may include valve frame structure withoutleaflets.

In accordance with another possible aspect of the invention, theapparatus may include a distal tip structure secured to a portion of thesheath structure that is most distant from an operator of the apparatus.The distal tip structure may have a vent from inside the sheathstructure to outside the apparatus for facilitating de-airing of aninterior of the sheath structure.

In accordance with still another possible aspect of the invention, theapparatus may include a distal tip structure secured to a portion of thesheath structure that is most distant from an operator of the apparatus,and a shaft for allowing the distal tip structure and said portion ofthe sheath structure to be moved distally away from the valve support.The shaft may include an articulation proximal to said portion of thesheath structure.

In accordance with certain other possible aspects of the invention,apparatus for delivering a collapsible and re-expandable prostheticheart valve to an implant site in a patient may include a valve supportstructure around which the valve is disposed in a collapsed condition,the valve support structure having axially spaced proximal and distalportions, with the proximal portion being closer than the distal portionto an operator of the apparatus. The apparatus may further include asheath structure surrounding the valve on the valve support structure.The apparatus may still further include means for moving the sheathstructure in a distal direction relative to the valve support structureto uncover the valve for expansion at the implant site.

In a case such as is mentioned in the preceding paragraph, the apparatusmay further include a second sheath structure surrounding the sheathstructure, and second means for moving the second sheath structure in aproximal direction relative to the valve support structure to uncoverthe sheath structure.

Further in a case such as is mentioned two paragraphs above, the valvesupport structure may include elements that extend radially outwardlyinto a tubular geometric shape in which a frame structure of thecollapsed valve is disposed, said elements being positioned to interferewith motion of the valve (parallel to a longitudinal axis of the tubulargeometric shape) relative to the valve support structure.

Still further in a case such as is mentioned three paragraphs above, themeans for moving may comprise an articulation proximal of the sheathstructure but distal of the valve support structure when the means formoving has moved the sheath structure to completely uncover the valve.

Further in a case such as is mentioned four paragraphs above, theapparatus may further include a distal tip structure secured to a distalend of the sheath structure, the distal tip structure defining a ventfrom inside the sheath structure to outside of the apparatus.

In accordance with certain still other possible aspects of theinvention, a method of operating apparatus for delivering a collapsibleand re-expandable prosthetic heart valve to an implant site in a patientmay include introducing the apparatus into the patient with the valvedisposed in a collapsed condition around a valve support structure, andwith a sheath structure surrounding the valve. The method may furtherinclude moving the sheath structure relative to the valve supportstructure to uncover the valve for expansion at the implant site.

In accordance with a further possible aspect of the invention, themethod may include moving the sheath structure relative to the valvesupport structure after expansion of the valve so that the sheathstructure covers the valve support structure. The method may thenfurther include withdrawing the apparatus from the patient.

In accordance with still another possible aspect of the invention, thevalve may be at a first location in the apparatus that is remote from anoperator the apparatus, and the moving may move the sheath structure toa second location that is more remote from the operator than the firstlocation. In such a case, during the introducing the sheath structuremay be covered by a second sheath structure, and the method may furtherinclude, prior to the moving, moving the second sheath structure to athird location that is closer to the operator than the first location.

In accordance with yet another possible aspect of the invention, themethod may further include passing additional instrumentation throughthe valve support structure to a location in the patient that is moreremote from an operator of the apparatus than the valve supportstructure.

In accordance with still another possible aspect of the invention, themethod may further include passing fluid through a portion of the valvesupport structure from a location (which is closer to an operator of theapparatus than the valve support structure) to the valve.

In accordance with yet another possible aspect of the invention, themethod may further include drawing a portion of the valve radiallyinwardly toward the valve support structure after the moving hasuncovered that portion of the valve.

Further features of the invention, its nature and various advantages,will be more apparent from the accompanying drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified isometric or perspective view of an illustrativeembodiment of portions of apparatus in accordance with the invention.

FIG. 2 is similar to FIG. 1 for another operating condition of the FIG.1 apparatus in accordance with the invention.

FIG. 3 is again similar to FIG. 1 for still another operating conditionof the FIG. 1 apparatus in accordance with the invention.

FIG. 4 is a simplified elevational view of portions of anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 5 is again similar to FIG. 1 for yet another operating condition ofthe FIG. 1 apparatus in accordance with the invention.

FIG. 6 is again similar to FIG. 1 for still another operating conditionof the FIG. 1 apparatus in accordance with the invention.

FIG. 7 is a view similar to FIG. 1 for portions of another illustrativeembodiment of apparatus in accordance with the invention.

FIG. 8 is similar to FIG. 7 for another operating condition of the FIG.7 apparatus in accordance with the invention.

FIG. 9 is a simplified elevational view of portions of still anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 10 is a simplified elevational view of portions of yet anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 11 is a simplified elevational view of portions of still anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 12 is a simplified elevational view of portions of yet anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 13 is a simplified isometric or perspective view of portions ofstill another illustrative embodiment of apparatus in accordance withthe invention.

FIG. 14 is a simplified isometric or perspective view of portions of yetanother illustrative embodiment of apparatus in accordance with theinvention.

FIG. 15 is a simplified isometric or perspective view of portions ofstill another illustrative embodiment of apparatus in accordance withthe invention.

FIG. 16 is a simplified elevational view of portions of yet anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 17 is similar to FIG. 16 for another operating condition of theFIG. 16 apparatus in accordance with the invention.

FIG. 18 is again similar to FIG. 16 for yet another operating conditionof the FIG. 16 apparatus.

FIGS. 19 and 20 are simplified elevational views, taken at right anglesto one another, of an illustrative embodiment of a component ofapparatus in accordance with the invention.

FIG. 21 is a simplified isometric or perspective view of the componentshown in FIGS. 19 and 20.

FIG. 22 is a simplified isometric or perspective view of an alternativeembodiment of the component shown in FIGS. 19-21 in accordance with theinvention.

FIG. 23 is a simplified isometric or perspective view of an illustrativeembodiment of another component of apparatus in accordance with theinvention.

FIG. 24 is a simplified isometric or perspective view of an alternativeembodiment of the FIG. 23 component in accordance with the invention.

FIGS. 25 and 26 are simplified isometric or perspective views ofillustrative embodiments of other components of apparatus in accordancewith the invention.

FIG. 27 is a simplified elevational view, partly in section, of anillustrative embodiment of portions of apparatus in accordance with theinvention.

FIG. 28 is a simplified perspective or isometric view of an illustrativeembodiment of portions of apparatus in accordance with the invention.

FIG. 29 is a simplified elevational view of an illustrative embodimentof portions of apparatus in accordance with the invention.

FIG. 30 is a view similar to FIG. 29 for another illustrative embodimentin accordance with the invention.

FIG. 31 is a simplified isometric or perspective view of portions of anillustrative embodiment of apparatus in accordance with the invention.

FIG. 32 is a simplified isometric or perspective view of other portionsof an illustrative embodiment of apparatus in accordance with theinvention.

FIG. 33 is a simplified elevational view of portions of an illustrativeembodiment of apparatus in accordance with the invention.

FIG. 34 is a simplified elevational view of other portions of anillustrative embodiment of apparatus in accordance with the invention.

FIG. 35 is a simplified elevational view of portions of anotherillustrative embodiment of apparatus in accordance with the invention.

FIG. 36 is a simplified elevational view of several subassemblies fromFIG. 35.

FIG. 37 is a simplified, partial, sectional view further illustratingcertain possible aspects of the invention.

FIG. 38 is a another simplified, partial, sectional view furtherillustrating certain possible aspects of the invention.

FIG. 39 is a simplified isometric or perspective view of an illustrativeembodiment of a component that may be included in apparatus inaccordance with the invention.

FIGS. 40 and 41 are simplified isometric or perspective views of anillustrative embodiment of another component that may be included inapparatus in accordance with the invention.

FIG. 42 is a simplified isometric or perspective view of an illustrativeembodiment of apparatus in accordance with invention and showing anotherpossible feature of such apparatus.

DETAILED DESCRIPTION

Examples of valves with which the present invention can be used areshown in Braido U.S. patent application Ser. No. 11/906,133, filed Sep.28, 2007, which is hereby incorporated by reference herein in itsentirety. Such valves typically include a relatively stiff frame (e.g.,of metal or other appropriate material(s)) and flexible leaflets (e.g.,of tissue or other appropriate material(s)) that are attached to theframe. Such valves may also include other components, such as layers ofadditional tissue (e.g., for buffering) and layers of fabric (e.g., topromote tissue in-growth). The FIGS. that form part of the presentdisclosure tend to concentrate on the frame of the depicted valves, andto omit or greatly simplify other valve components such as the leaflets,other layers of tissue and/or fabric, sutures, etc. This is done tosimplify the FIGS. and to reduce the degree to which the valve obscuresfeatures of the present structures. It should be understood, however,that wherever a valve frame is shown herein, all other components of acomplete prosthetic valve are also present with the frame, althoughthose other components are not depicted (either at all or in fulldetail) for the reasons mentioned above.

The present invention will be shown and described herein primarily inthe context of prosthetic aortic valves. It will be understood that theinvention can also be applied to prostheses for other valves in theheart. The invention will sometimes be referred to herein in the contextof introducing a replacement (prosthetic) aortic valve into a patient'sheart via the left ventricle at the apex (lower extremity) of thepatient's heart. From such an apical access point, the valve is movedupward to the vicinity of the annulus of the patient's native aorticvalve, where the replacement heart valve is released from the deliveryapparatus and thereby implanted in the patient. (The word “upward” andother similar terms are used as though the patient were standing,although the patient will of course not be standing during a heart valvereplacement procedure.) It will be understood that this (exemplary)implant site can be approached in other ways (e.g., percutaneoustransluminal, transaortic, transfemoral, or using any incision along thelength of the ascending or descending aorta).

The delivery apparatus and methods of this invention may allow theprosthetic heart valve to be delivered and released in different ways.For example, a construction of the delivery apparatus may allowdifferent parts of the replacement heart valve to be released beforeother parts are released, and the delivery apparatus may allow the orderin which different parts of the valve are released to be varied indifferent situations. In all cases the word proximal is used to refer tothe part of the valve or the part of the valve delivery apparatus thatis closer to the operator (medical practitioner) of the apparatus. Theword distal is used to refer to the part of valve or apparatus that isfarther from the operator. The delivery apparatus may allow the distalpart of the valve to be released from that apparatus before or after theproximal part of the valve is released. Also, the orientation of thevalve in the delivery apparatus may be different in differentsituations. In some cases the part of the valve that will be upstream inthe patient's blood flow when the valve is implanted may be locatedproximally in the delivery apparatus. In other cases the part of thevalve that will be downstream in the patient's blood flow when the valveis implanted may be located proximally in the delivery apparatus.Various combinations of the foregoing options are possible, so that, forexample, the portion of the valve that is released from the deliveryapparatus first may be (1) proximal and downstream, (2) distal anddownstream, (3) proximal and upstream, or (4) distal and upstream.

FIG. 1 shows an illustrative embodiment of the distal portion ofprosthetic valve delivery apparatus 100 in accordance with theinvention. FIG. 1 shows apparatus 100 containing a prosthetic aorticheart valve 10 prior to deployment of that valve. Valve 10 is visible inapparatus 100 because an outer, hollow, tubular sheath 110 a-b ofapparatus 100 is shown as though substantially transparent, althoughsheath 110 a-b could in fact be opaque. Only the distal portion ofdelivery apparatus 100 is shown in FIG. 1. It will be understood thatapparatus 100 continues in the proximal direction (downward and to theleft as viewed in FIG. 1), ultimately extending to operator controls,which can be used by an operator (medical practitioner) to (remotely)control the distal portion of the apparatus that is visible in FIG. 1.Whereas the distal portion of apparatus 100 typically enters thepatient's body by any of several different routes, the proximal controlstend to remain outside the patient's body where they can be manipulatedby the operator.

Principal components of valve 10 are relatively stiff frame 20 andflexible leaflets 30. Because valve 10 is inside delivery apparatus 100,valve 10 is shown in its undeployed, circumferentially relatively small(collapsed) condition. Frame 20 includes three major portions: (1)upstream (blood in-flow side) hollow annular portion 20 a, (2)downstream (blood out-flow side) hollow annular portion 20 c, and (3) anannular array of axially extending struts 20 b that extend between andconnect upstream and downstream portions 20 a and 20 c. When releasedfrom apparatus 100, upstream portion 20 a annularly expands in thevicinity of the patient's native aortic valve annulus to engage thepatient's native tissue in that vicinity. Similarly, when released fromapparatus 100, downstream portion 20 c annularly expands in thepatient's aorta downstream from the valsalva sinus and engages thattissue of the aorta. Further, when valve 10 is released from apparatus100, struts 20 b pass through the patient's valsalva sinus so that thesestruts continue to link the other portions 20 a and 20 c of the frame.

The flexible leaflets 30 of the valve 10 are mounted on upstream frameportion 20 a so that they are at least primarily inside that frameportion.

Delivery apparatus 100 includes a central-most shaft (not visible inFIG. 1, but coaxial inside shaft 120 and axially movable relativethereto (see FIG. 5 where this central-most shaft is partly visible at132)). Atraumatic tip 130 is securely mounted on the distal end of thiscentral-most shaft. If desired, delivery apparatus 100 may be insertableinto the patient over a guide wire that was previously introduced intothe patient. For this purpose, tip 130 may have an axial hole through itand other upstream components may be similarly hollow or provided withan interior lumen. For example, a through hole in tip 130 may connectwith a hollow lumen through central-most shaft 132, which lumen mayextend proximally until it emerges at the proximal end of the apparatus.

The distal portion 110 b of a split outer sheath of apparatus 100 issecurely attached to tip 130 and extends proximally therefrom to sheathsplit or parting line 110 c. In particular, parting line 110 c isannular and located in the vicinity of the strut portion 20 b of valveframe 20. Parting line 110 c is at the location where the proximal endof distal sheath portion 110 b meets the distal end of proximal sheathportion 110 a, and where these two portions of the sheath can be pulledapart when desired. The adjacent ends of these two sheath portions 110 aand 110 b may initially abut one another at parting line 110 c, or theymay initially axially overlap one another in the vicinity of partingline 110 c. (As used herein, the term axially or the like means parallelto the longitudinal axis of apparatus 100.) From the foregoing it willbe seen that when inner-most shaft 132 is moved axially, the entiresubassembly of shaft 132, sheath portion 110 b, and tip 130 movestogether as a unit.

Annularly around the (invisible in FIG. 1) central-most shaft 132 onwhich tip 130 is mounted is another axially extending longitudinal shaft120. Shaft 120 is axially movable relative to the above-mentionedcentral-most shaft. An annular plunger 140 is securely mounted on thedistal end of shaft 120. Plunger 140 includes (1) a distal section 140 ahaving a relatively large outer diameter; (2) a proximal section 140 chaving an outer diameter that alternates between relatively large andrelatively small as one proceeds in the annular direction around thatsection of the plunger; and (3) an intermediate section having arelatively small outer diameter. The above-mentioned relatively largediameters fit with only a relatively small clearance inside sheath 110b. The above-mentioned relatively small diameters are small enough toreadily accept the thickness of valve frame 20 between the plungersurface having such relatively small diameter and the inner surface ofsheath 110 b. Intermediate portion 140 b is axially long enough torelatively snugly receive the axial length of the distal portion 20 c ofvalve frame 20. Similarly, struts 20 b of valve frame 20 can passaxially through the reduced-diameter regions of the proximal portion 140c of plunger 140.

From the above description it will be appreciated that the distalportion 20 c of valve frame 20 is captured radially between the outersurface of the intermediate portion 140 b of plunger 140 and the innersurface of the distal sheath portion 110 b, and that it is capturedaxially between the distal portion 140 a of plunger 140 and therelatively large diameter portions of the proximal portion 140 c of theplunger. There is even rotational securement of valve frame 20 relativeto plunger 140 as a result of struts 20 b passing through proximalplunger portion 140 c between relatively large diameter regions of thatproximal portion.

Proximal of valve 10 is another plunger 150 securely mounted to shaft120 and coaxial (annular) around that shaft. Proximal plunger 150 has arelatively large outer diameter that fits within proximal sheath portion110 a with relatively small clearance.

The structure shown in FIG. 1 can be constructed with any desired degreeof lateral flexibility (the opposite of lateral stiffness). (Lateralflexibility refers to the ability of structure 100 to deflect (bend)transverse to its longitudinal axis.) For example, if delivery apparatus100 is intended for percutaneous delivery of valve 10 into a patient,apparatus 100 may be required to have a relatively high degree oflateral flexibility so that the apparatus can follow the inside ofcurving vascular passageways inside the patient to reach the desiredimplant site of valve 10. On the other hand, if apparatus 100 isintended for use in transapical delivery of valve 10 into the patient,it may be desirable for apparatus 100 to be somewhat laterally stifferthan would be best for percutaneous use.

FIG. 2 shows one example of how the FIG. 1 apparatus may be operated tobegin to deploy valve 10 in a patient. In this example, when valve 10 isat the intended implant site in the patient, proximal sheath 110 a ispulled back proximally relative to everything else in FIG. 2. Thisbegins to expose the proximal portions of valve 10. However, the distalportions of valve 10 remain securely held by the distal portions ofdelivery apparatus 100. This manipulation of delivery apparatus 100 cancontinue until (as shown in FIGS. 3 and 4) the entire proximal portionof valve 10 has been exposed. FIG. 3 shows this result in simplifiedform, which omits depiction of the consequent radial enlargement of theproximal portion of valve 10. However, FIG. 4 does show the proximalportion 20 a of valve 10 enlarging radially outward as a result of itsrelease from constraint by proximal sheath 110 a. (All of theenlargement of the valve depicted and/or described herein may be due toresilient and/or shape-memory enlargement of valve frame 20.Shape-memory enlargement may be partially controlled by controlling theambient temperature that valve frame 20 is exposed to.)

FIG. 5 shows further deployment of valve 10 (after the condition shownin FIGS. 3 and 4 has been reached). (Again, FIG. 5 is simplified by notshowing the radial enlargement of the proximal portion of valve 10.) InFIGS. 5 tip 130 is pushed distally relative to other structure in theFIG. by pushing the shaft 132 (on which tip 130 is mounted) distallyrelative to shaft 120. (Shaft 132 was mentioned earlier, but it was notvisible in the FIGS. prior to FIG. 5.) As tip 130 moves distally, itcarries distal sheath portion 110 b with it, thereby beginning to exposethe distal portion of valve 10, which distal valve portion (at leastinitially) continues to be held securely by plunger 140 inside distalsheath portion 110 b.

FIG. 6 shows the condition of the FIG. 5 apparatus after distal sheath110 b has moved completely beyond the distal end of valve 10 and thevalve is therefore completely exposed and deployed in the patient(except that FIG. 6 again omits the fact that at this stage valve 10will have annularly enlarged along its entire length to engagesurrounding native body tissue of the patient, thereby anchoring thevalve at the desired implant site in the patient). After valve 10 hasthus annularly enlarged and deployed in the patient, the valve deliveryapparatus 100 can be withdrawn from the patient. To facilitate suchwithdrawal, proximal sheath portion 110 a can be pushed distallyrelative to other components through the leaflet structure 30 of thevalve. Distal tip 130 and distal sheath portion 110 b can then be pulledproximally relative to other components until the proximal end of sheath110 b meets the distal end of sheath 110 a (or, as in other embodiments,until distal sheath portion 110 b is inside proximal sheath portion 110a), thereby again giving delivery apparatus 100 a smooth outer surface.This facilitates withdrawal of apparatus 100 in the proximal directionthrough deployed valve 10 without compromising leaflets 30.

FIG. 7 shows two possible variations from earlier-described embodiments.(The general reference number 100 continues to be used for the deliveryapparatus, even though there are some variations from earlierembodiments.) One of these possible variations is use of proximal endretainer 150 so that the proximal end of valve 10 can rest on it,thereby controlling the collapsed inside diameter of the valve. Theother possible variation is relocating the split 110 c between theproximal sheath portion 110 a and the distal sheath portion 110 b sothat split 110 c is proximal of valve 10. The valve is now deployedsolely by moving distal sheath portion 110 b distally to a finalposition like that shown in FIG. 8. In other words, moving distal sheathportion 110 b (which initially completely covers valve 10) in the distaldirection completely uncovers the valve for deployment in the patient.(FIG. 8 again omits depiction of the annular enlargement of valve 10that follows from moving sheath 110 b away to expose the valve.)

Returning to embodiments like those shown in FIGS. 1-6, FIG. 9 shows apossible alternate use. This alternate use is deployment of the distalportion 20 c first. This is accomplished by shifting elements 130, 132,and 110 b distally relative to other components before shifting sheathportion 110 a proximally. This is the condition of the apparatus that isshown in FIG. 9; and as that FIG. shows, it results in release andannular enlargement of the distal portion 20 c of valve 10, while theproximal portion 20 a is still confined within proximal sheath portion110 a. The condition shown in FIG. 9 will be followed by shifting sheathportion 110 a proximally, which exposes and deploys (i.e., allowsannular enlargement of) the proximal portion 20 a of valve 10.

FIG. 10 shows yet another alternative in which sheath 110 is not dividedinto two axially different parts. Instead, in FIG. 10 one sheath 110extends all the way to distal tip 130. However, sheath 110 can be pulledproximally back from distal tip 130 when valve 20 is at the desiredlocation in the patient. FIG. 10 shows such proximal retraction ofsheath 110 beginning. This exposes (and deploys) valve 20 distal endfirst.

FIGS. 11 and 12 show some possible ways that the parts 110 a and 110 bof an axially split sheath 110 may come together. In FIG. 11 a distalportion of part 110 a is slightly enlarged so that it can fit around theoutside of the proximal portion of part 110 b. In the alternative shownin FIG. 12 this arrangement is reversed. In particular, in FIG. 12 theproximal portion of part 110 b is slightly enlarged so that it can fitaround the outside of the distal portion of part 110 a. Other variationsare possible, such as having the ends of parts 110 a and 110 b the samesize so that they simply abut one another with no overlapping (as theydo in FIGS. 11 and 12).

FIG. 13 shows possible construction of proximal end retainer 150 withholes 152 extending axially through. These holes can allow fluid to passfrom proximal portions of the delivery apparatus, through retainer 150,to reach valve 20. For example, such fluid can have temperature that iscontrolled to cool or warm the valve to help it deploy into the patientin a controlled manner (e.g., using shape-memory properties of the frame20 of valve 10 when that frame is made of a material like nitinol).

FIG. 14 is an enlargement of distal end retainer 140 in which itspossible construction can perhaps be seen more clearly.

FIG. 15 shows an alternate design in which a “bumper” 140′ or 150′ ismounted on shaft 120 adjacent each axial end of the frame 20 of valve10. Each bumper has a face that is perpendicular to the longitudinalaxis of the apparatus and that faces toward the axial end of valve frame20 that is adjacent to that bumper. These bumper faces keep valve 10trapped at the desired axial location in the delivery apparatus untilthe valve is exposed and therefore able to annularly enlarge as a resultof the axial shifting of sheath portions 110 a and 110 b. The faces ofbumpers 140′ and 150′ that face away from valve 10 are preferablyconical as shown. This helps sheath portions 110 a and 110 b to againcome together after valve deployment, when a smooth exterior ofapparatus 100 is again desired to facilitate withdrawal of the deliveryapparatus from the patient.

FIGS. 16-18 illustrate another possible construction of deliveryapparatus 100. In this construction proximal sheath part 110 a initiallyextends distally all the way to distal tip 130. Inside the distalportion of sheath 110 a, distal sheath portion 110 b extends proximallyfrom distal tip 130 to initially completely cover valve 10 (i.e., itends with some overlap of the distal part of plunger 150). Valve 10 isdeployed by first pulling sheath 110 a back proximally so that itsdistal end is adjacent plunger 150 as shown in FIG. 17. No part of thevalve is yet deployed, however, because the valve is still entirelyinside sheath 110 b. Then distal tip 130 and sheath 110 b can be pusheddistally to begin to expose valve 10 as shown in FIG. 18. This exposureof the valve starts at the proximal end (as shown in FIG. 18), and thencontinues until the valve is completely exposed and deployed. (Onceagain, FIG. 18 omits depiction of the annular enlargement of valve 10that occurs when the valve is exposed.)

A possible variation of what is shown in FIGS. 16-18 is to make distalsheath 110 b shorter so that the proximal end of the valve begins todeploy when the proximal sheath 110 a is retracted beyond the proximalend of distal sheath 110 b.

FIGS. 19-21 show several views of an illustrative embodiment of proximalretainer 150. FIG. 22 shows an alternative embodiment of retainer (likethe embodiment used in FIG. 16-18). FIG. 23 shows an illustrativeembodiment of distal retainer 140. FIG. 24 shows an alternativeembodiment of distal retainer 140 including an annular array of radiallyextending holes 142 that are usable in an embodiment of deliveryapparatus 100 that permits valve 10 to be recollapsed after it has beendeployed or partly deployed (e.g., to allow repositioning or removal ofthe valve). Delivery apparatus features like this are described in moredetail later in this specification.

FIG. 25 is another view of an illustrative embodiment of a typical oneof above-described bumpers 140′/150′.

FIG. 26 is another view of an illustrative embodiment of distal tipmember 130.

FIG. 27 is a longitudinal sectional view of an embodiment like the oneshown in FIGS. 7 and 8.

FIG. 28 shows an illustrative embodiment of structures in accordancewith certain possible aspects of the invention for facilitatingrecollapsing of a valve 10 for such purposes as allowing the valve to berepositioned in the patient or removed from the patient after it hasbeen at least partly deployed in the patient but before final release ofthe valve from the delivery apparatus. FIG. 28 shows only the distalpart 20 c of the valve 10 (the other parts of the valve being omittedfor clarity). As shown in FIG. 28 (and also FIG. 29), three strands 210a-c of flexible recollapsing material are threaded through the distalpart 20 c of the frame (stent) of valve 10. For example, FIG. 29 moreclearly shows that each of these strands 210 is threaded through arespective one of three different arcuate segments of the annulus ofdistal part 20 c. Eyelets (visible in FIG. 28) may be provided in part20 c for threading strands 210 through. Each strand may follow a wovenor serpentine trajectory, alternately into and out of the interior ofpart 20 c, as one proceeds in the annular direction around part 20 c.The ends of each strand 210 that extend from part 20 c enter the lumenof delivery system structure 120 via radial apertures 142 through theside wall of distal retainer 140 as in FIG. 24, which distal retainer isattached to structure 120. Once inside the above-mentioned lumen, thesestrand ends extend along the lumen in the proximal direction to wherethey become accessible to control by the operator of the deliveryapparatus from outside the patient's body. It is preferred that theapertures (like 142 in FIG. 24) be in approximately the same plane(substantially perpendicular to the longitudinal axis of the deliveryapparatus) as the threading of strands 210 through part 20 c. In thisway, when the ends of strands 210 are pulled proximally (parallel to thelongitudinal axis of the delivery apparatus), the above-mentionedapertures (like 142) convert the tension in the strands to radial inwardforces on part 20 c. Because these forces are radial, they have thegreatest efficiency in pulling in on part 20 c and thereby re-collapsingthat part (e.g., against the outer surface of component 140). Suchradial inward force is also preferred because it tends to avoid axialshifting of valve 10 during any re-collapsing operation.

The number of strands 210 and/or the pattern in which they attach topart 20 c can differ from what is shown in FIGS. 28 and 29. For example,FIG. 30 shows the use of many more than three strands 210, and FIG. 30also shows each strand having basically only one point of attachment topart 20 c. Each such point of attachment is preferably radially out fromthe aperture (like 142) through which the associated strand 210 entersthe lumen inside structures 120/140, and each point of attachment andthe associated aperture (like 142) are on an associated radius that ispreferably substantially perpendicular to the longitudinal axis of thedelivery apparatus.

If, after valve 10 has been partly deployed in the patient, the locationof the valve does not appear (e.g., fluroscopically) to be as desired,the valve can be recollapsed back onto the delivery apparatus by pullingon the proximal ends of strands 210. The valve can then either beremoved from the patient (by withdrawing the delivery apparatus from thepatient), or the valve can be relocated in the patient (by manipulatingthe delivery apparatus to produce such relocation). Such valve removalor relocation may also include again closing the sheath structure(s) 110a and/or 110 b around the outside of the valve. Assuming that valverelocation is the objective, when the valve is at the new location, itcan be expanded again by releasing the tension on strands 210 and, ifsheath 110 a and/or 110 b was re-closed around the valve, re-openingthat sheath structure. When the valve is finally satisfactorilypositioned in the patient, the valve can be finally released from thedelivery apparatus by pulling one proximal end of each strand 210proximally until the other end of the strand emerges out of the deliverysystem at the operator controls end.

Although the above valve retrieval/repositioning structure is shownapplied to valve part 20 c, it will be understood that it canalternatively or additionally be applied to other valve parts such as 20a.

Strands 210 can be made of any suitable, sufficiently strong,sufficiently flexible, and sufficiently fine material and construction.Examples are wire (e.g., of nitinol), suture line, nylon line, or thelike. The number and placement of the holes (like 142) for strands 210to pass through the side wall of structure like 120/140 can beappropriate for the number and placement of the strands used.

The following is a description of an illustrative embodiment of theproximal (operator control, always outside the patient's body) portionof delivery apparatus 100, especially with reference to FIGS. 31-36.

Element 110 a-b is again the main outer shaft of the delivery apparatus,with part 110 a being the proximal sheath. This structure can facilitateintroduction of fluids, which can be used to prep the delivery apparatusso that no gas (e.g., air) bubbles are introduced into the patient'scirculatory system. Element 110 a-b can also be used as a vessel thathouses saline, which keeps valve 10 hydrated from the time it is loadedinto the system until it is implanted in the patient. Structure 110 amay also function as the proximal sheath, which controls/houses thecrimped proximal end of the valve.

Component 320 is an end cap that (1) prevents fluid from leaking, (2)allows shaft 120 to pass through, and (3) allows connection to manifold370.

Shaft or conduit 120 controls the crimped valve's axial movement fordeployment and retrieval. Structure 120 facilitates introduction offluids through port 360 a, which aids in flushing and prepping thedelivery apparatus.

Hub 340 is attached/integrated with shaft 120 and has a standard luerconnection for connecting manifold 360.

Inner lumen 132 may be a hypo-tube or any other conduit that is notlimited to but allows introduction of ancillary devices such as guidewires, embolic protection devices, a balloon for pre-dilation of theimplant site, fluids, etc. Also, shaft 132 is the means by which thedistal sheath 110 b is moved distally to release the distal end of thecrimped valve. FIG. 35 shows an alternative having a valve connector 390attached to the proximal end of inner lumen 132 (in lieu of moldedhandle 134 as in FIGS. 32-34). FIG. 36 shows another alternative inwhich manifold connectors 390, etc., can be attached to the proximal endof inner lumen 132 (again in lieu of molded handle 134). The FIG. 36embodiment can provide a through port into the proximal end of innerlumen 132, whereby fluids and other devices of the types mentionedearlier (e.g., guide wires, embolic protection devices, balloons forpre-dilation of the implant site, etc.) can enter and pass through theentire length of the delivery apparatus (e.g., while delivery apparatus100 is in place in the patient).

Manifold 360 functions as a fluid-tight valve control that forms a tightseal on shaft 132 when knob 380 (proximal occurrence) is turnedclockwise. When locked (tightened), shaft 132 cannot be moved. Lever 390(proximal occurrence) controls opening and closing of the fluid entryport into lumen 120. Fluids are introduced from this port, which has astandard luer for ancillary device attachment (e.g., syringes, etc.)

Manifold 370 functions as a fluid-tight valve control that forms a tightseal on shaft 120 when knob 380 (distal occurrence) is turned clockwise.When locked (tightened), shaft 120 cannot be moved. Lever 390 (distaloccurrence) controls opening and closing the fluid entry port into lumen110.

Knobs 380 (both occurrences) cause fluid to escape, but also allow freemovement of the shafts passing through them. When these knobs areclosed, they lock the associated shafts in place and prevent fluidleakage. They can be opened sufficiently to allow relative movement ofthe associated shafts without significant fluid leakage.

Valve levers 390 (both occurrences) can be opened to allow introductionof fluids. When closed, they prevent fluid introduction or leakage.

Although the foregoing tends to show valve 10 oriented in deliveryapparatus 100 so that what will be the downstream portion 20 c of thevalve (in terms of blood flow through the valve after it has beenimplanted in a patient) is toward the distal end of the deliveryapparatus, it will be understood that this orientation of the valve canbe reversed if desired. The valve orientation that is generally shownherein is suitable, for example, for implanting an aortic valve via anantegrade approach (i.e., delivery apparatus 100 inserted in the bloodflow direction). An example of such antegrade delivery in insertion ofdelivery apparatus 100 through an incision in the so-called apex of theheart (e.g., near the bottom of the left ventricle) and passage of thedistal portion of delivery apparatus 100 up through the left ventricleuntil valve 10 is positioned adjacent the patient's native aortic valveannulus, where the valve can be deployed from the delivery apparatus andthereby implanted in the patient. (This may be referred to as atransapical approach.) A typical final disposition of the valve is withthe extreme lower portion of valve frame part 20 a flared out below andlodged against the native valve annulus, with the more distal portion offrame part 20 a passing tightly through the native annulus, with struts20 b passing through the native valsalva sinus, and with valve framepart 20 c lodged tightly in the native aorta downstream from thevalsalva sinus.

Alternatively, however, and as noted above, the orientation of valve 10in delivery apparatus can be reversed, and then the implant site can beapproached in the retrograde direction (i.e., opposite the direction ofblood flow). For example, the distal portion of the delivery apparatuscan arrive at the implant site in the patient (e.g., the location of thenative aortic valve) after passing through the patient's aorta. Accesscan be via an incision in the side wall of the aorta, or from a moreremote location in the patient's circulatory system that leads to theaorta (so-called percutaneous or transluminal delivery). The ultimate,final disposition of valve 10 in the patient can be the same as was justdescribed above. The delivery apparatus of this invention allowsdifferent portions of the valve to be released in whatever order isdesired, which order may differ depending on whether the antegrade orretrograde approach is used.

FIG. 37 illustrates in more detail a point made earlier regarding howvalve support structure such as 140 can be constructed to cooperate withcollapsed valve 10 to substantially prevent the collapsed valve frommoving relative to the delivery apparatus parallel to the longitudinalaxis of the valve and the delivery apparatus. FIG. 37 shows structurelike that shown, for example, in FIGS. 1-10, 14, 16-18, 23, 24, 27, and31. In particular, FIG. 37 shows a simplified, partial, sectional viewof a distal portion of such structure. FIG. 37 shows that a distalportion 20 c of the frame of collapsed valve 10 is disposed in a recessin the outer surface of the distal retainer 140 portion of the valvesupport structure of the delivery apparatus. For reference, a geometriclongitudinal axis of valve 10 and delivery apparatus 100 is shown at101. (FIG. 37 omits depiction of the sheath or sleeve structure 110 thatmay be present around the outside of which is shown in FIG. 37.)

The portion of valve frame 20 that is disposed in the above-mentionedrecess in valve support structure 140 has first and second surfaceportions 21 a and 21 b that face in respective opposite first and seconddirections along axis 101. Valve support structure 140 (in particularthe above-mentioned recess) has third and fourth surface portions 141 aand 141 b that respectively face in the second and first directions. Thefirst and third surface portions 21 a and 141 a are positioned adjacentto and facing one another. Similarly, the second and fourth surfaceportions 21 b and 141 b are positioned adjacent to and facing oneanother. These relationships among surfaces 21 a/b and 141 a/bsubstantially prevent relative movement of valve 10 and valve supportstructure 140 along axis 101 while the valve is disposed around thevalve support structure in the collapsed condition. For example, thissecure holding of the valve means that the valve can be placed wheredesired in the patient, and then any sheath or sleeve structure like 110a/b can be moved relative to the valve and the valve support structurewithout disturbing the desired location of the valve in the patient.This may be especially important in cases in which the valve frame isresiliently biased to press outwardly against the surrounding sheath.Without secure positioning of the valve relative to its supportstructure, the valve might be dragged with the sheath when the sheath isshifted relative to the valve support. This could disturb the locationof the valve in the patient and/or make it difficult to get the valveout of the sheath.

FIG. 38 brings out the same point (made above in connection with FIG.37) for embodiments like those shown in FIG. 15. Thus FIG. 38 shows thatthe frame 20 of valve 10 is received in a recess between the distalbumper 140′ and the proximal bumper 150′ of the valve support structure.Valve frame 20 has first and second surfaces 21 a and 21 b that face inrespective opposite first and second directions along axis 101. Valvesupport structure 120/140′/150′ has third and fourth surface portions141 a and 151 b that respectively face in the second and firstdirections. The first and third surface portions 21 a and 141 a arepositioned adjacent to and facing one another. Similarly, the second andfourth surface portions 21 b and 151 b are positioned adjacent to andfacing one another. These relationships among surfaces 21 a/b and 141a/151 b substantially prevent relative movement of valve 10 and valvesupport structure 120/140′/150′ along axis 101 while the valve isdisposed around the valve support structure in the collapsed condition.For example, this secure holding of the valve means that the valve canbe placed where desired in the patient, and then any sleeve structurelike 110 a/b can be moved relative to the valve and the valve supportstructure without disturbing the desired location of the valve in thepatient.

Another way to describe possible features of the invention of the typehighlighted by FIGS. 37 and 38 is to say that the valve supportstructure has elements that extend radially out at least into a tubulargeometric shape in which the frame of the collapsed valve is disposed onthe valve support structure. These elements are positioned to positivelyinterfere with and thereby prevent relative axial movement of thecollapsed valve and the valve support structure. Specific examples ofsuch outwardly projecting elements on the valve support structure arethe outer portions of elements 140 a, 140 c, 140′, and 150′. Theseelements operate to hold the collapsed valve in a fixed axial positionon the valve support structure of the delivery apparatus by contactingaxially facing surfaces of the valve frame if the valve attempts to moveaxially relative to the support structure.

FIGS. 39-41 illustrate further possible features of the invention. Theseare holes 149 that extend longitudinally through valve support structure140 and/or holes 139 that extend longitudinally through distal tipstructure 130 and that can be used to facilitate de-airing of theapparatus prior to use. For example, the apparatus can be heldvertically, with distal tip 130 up, during such de-airing. A salinesolution can be introduced into the bottom of sleeve 110 (e.g., viavalve 390 or the like). As the saline level rises in the apparatus, airis forced out via vent holes 139. Holes 149 ensure that air and salinefrom below support 140 can pass that support and reach distal tip 130.When saline begins to flow out of vent holes 139, it is known that allof the air is out of the apparatus. (The interior of shaft 120 can besimilarly de-aired by a parallel operation that includes introducingsaline into the lower end of shaft 120 so that all air in that shaftalso exits from the apparatus via vent apertures 139.)

FIG. 42 illustrates yet another possible feature in accordance with theinvention. This is making shaft 132 so that it can articulate (bendrelatively easily) in an articulation area or location 132 a. Thisarticulation location 132 a is preferably somewhat proximal of theproximal end of sheath portion 110 b. The purpose of this is to allowdistal structures 130, 110 b, and the portion of shaft 132 that isdistally beyond articulation 132 a to deflect laterally in order tosomewhat follow the curvature of the patient's aortic arch when theseelements are pushed distally into that arch to expose valve 10 fordeployment in the vicinity of the patient's native aortic valve annulus,etc. This helps reduce resistance to distal motion of elements 130 etc.that might otherwise result from contact of the aortic arch by thoseelements.

The following recapitulates and extends various aspects of what has beensaid above.

This invention relates to a collapsible/expandable valve delivery systemwhich can collapse, retain, maintain, transport, deploy, release, andhelp anchor a collapsible valve via a minimally invasive surgical portaccess or a percutaneous approach.

The system includes several components working together to facilitateaccess, delivery, deployment, expansion, and retrieval (if desired) ofthe collapsed valve. The delivery system has several elongated shaftsand conduits that retain and facilitate precise deployment (among otherfunctions) of the collapsed valve located at the distal end of thedelivery apparatus. At the proximal end, several shafts/conduits slideover/relative to one another, which controls the advancement,deployment, fluid delivery, and recollapse of the valve. The valve ismounted onto the middle shaft utilizing specially designed retainers.The collapsed valve is retained in its collapsed condition via twotubular sheaths. The two sheaths collectively cover, contain, andprotect the entire valve. The two sheaths move in a manner that givesthe operator flexibility in deploying the valve's proximal or distal endfirst. Some embodiments use only one sheath.

The invention allows flexibility in implanting the replacementprosthetic valve using an antegrade or retrograde approach. The systemhas multiple lumens that connect manifold ports at the proximal end ofthe delivery apparatus to an opening or port at the distal end (tip).These lumens can be utilized for various functions such as delivery offluids (temperature-controlled saline, contrast, etc.) and deployment ofembolic protection devices, balloons for valvuloplasty, etc.

The delivery system can be manufactured from materials that are known tobe biologically compatible for short-term human interaction, because thedelivery device is not a permanent implant. Considerations to materialselection are given because this device will come in contact with apermanent implant (prosthetic valve).

Manufacturing Steps: The delivery apparatus can be manufactured using acombination of extruded, injection molded, insert molded, machined,drawn surgical grade SS tubing, and other parts. The device componentscan fit together using various means of mechanical, thermal, or chemicalbonding (interference fit, adhesion, welding, tabs, slots, heat bonding,etc.) to facilitate building a seamless working system.

Operational Steps: The delivery apparatus can be introduced from any ofthe previously described approaches. Once satisfactory axial and radialpositioning are achieved, the deployment sequence begins. The valve canbe deployed proximal-end-first or distal-end-first. In the aortic valvecase (and depending on the valve's design and/or geometry), it ispreferred to deploy the valve's proximal end first in order for it toflare out. In doing so, the delivery apparatus can be advanced forwardslightly until resistance is felt. This tactile feedback to the operatoris an indication that optimal axial alignment has been achieved as thevalve's skirt is sub-annular of the native valve. While maintaining aslight pressure forward on the delivery apparatus to maintain thevalve's axial position, the distal end can now be deployed by advancingthe distal sheath forward. During proximal and/or distal end deployment,temperature-controlled saline can be infused to facilitate a slow,controlled deployment of a temperature-sensitive nitinol valve frame.This can prevent sudden “snap open” of the valve, which may be undesiredbecause it may cause a dissection or other damage at the implant site.The saline temperature can be slowly increased to ultimately reach bodytemperature. This allows the valve to expand to its fully expanded andoptimal geometry.

While the valve is partially or fully deployed but not fully released,it is possible to recapture it for repositioning or full retrieval ifdesired. Specially designed eyelets in the valve frame can facilitatethe use of members made from appropriate materials such as thin nitinolwire, fish line, stainless steel wire, etc., which are attached in amanner that can control the recollapse of the valve. Once recollapsed,the valve can be repositioned or fully retrieved.

The delivery system is preferably designed around a durable andefficient valve design, thus not compromising any of the valve'slong-term implant performance requirements. The delivery systempreferably gives the operator the flexibility and freedom to control thedeployment of the valve based on the chosen approach, patient anatomy,and disease state, among other important considerations. The systempreferably offers several desirable features that make the valve easierto deliver and retrieve and accommodate supplemental and existingancillary devices that may be used to successfully complete theprocedure.

This delivery device design can be used in a femoral access, transapicalaccess, transseptal access, or a direct small port access in theascending aorta. With the preferred delivery system design, access toany of the heart's valves (aortic, mitral, pulmonary, and tricuspid) canbe achieved for the purposes of repair and/or replacement of defectivenative valves.

The following is a recapitulation of various possible features of theinvention.

-   -   Low-profile delivery system for collapsing, maintaining,        delivering, deploying, repositioning, and retrieving (if        desired) collapsible/expandable valves.    -   Delivery system can be fine-tuned to the delivery approach        (retrograde or antegrade).    -   Radio-opaque markers can be placed in strategic areas and around        the valve for guidance and visualization of valve and delivery        system distal end under fluoroscopy or other visualization        systems.    -   Capabilities in fully deploying the valve but not releasing it        when repositioning or full recapture for retrieval is desired.    -   Delivery system with multi-lumen capabilities to facilitate        procedural support by using ancillary devices such as guide        wires, balloon catheters, embolic protection devices, fluids        delivery (flushing or visualization), etc.    -   Several shafts/lumens moving relative to one another as        follows: (1) Outer shaft: will sheath, collapse, and release        valve; creates a conduit for flushing fluid around the        valve. (2) Middle shaft: to advance and retract crimped valve        relative to outer and inner shafts. (3) Inner shaft: to advance        distal sheath for deployment of valve's distal end; also has a        lumen to allow advancement over a wire, as well as a conduit for        fluid delivery.    -   Valve is secured in place using sheaths and retainers. Retainers        are mounted on the middle shaft and move with the valve. Sheaths        move over the crimped valve.    -   Movable sheaths that function as valve retaining/collapsing        mechanism. Also can maintain and protect the valve in the        collapsed state. Create the outer edge of a conduit for fluids        such as temperature-controlled saline.    -   A unique split sheath design (proximal and distal sheath        halves). The distal half is attached to the tip, which is also        attached to an elongated shaft that is controlled and actuated        at the proximal end. Pushing this sheath distally deploys the        distal end of the valve. The sheath other half is attached to        the remainder of the delivery apparatus and moves proximally        relative to the valve, which deploys the proximal end of the        valve.    -   Features that control the valve's rotational (angular)        orientation within the delivery system so it can be deployed        with the correct radial orientation (e.g., to align with native        valve commissures and avoid coronary artery obstruction).    -   Capability of opening and closing off access to any of the lumen        ports back at the manifold connector.    -   Capability to lock the shafts of the delivery apparatus in        position relative to one another, which also seals conduits, in        addition locking in position.    -   Proximal valve retainer: (1) Centers the proximal sheath on the        main delivery apparatus longitudinal axis. (2) Allows fluids        passage during delivery apparatus preparation and during        administration of temperature-controlled saline. (3) Tapered        ends to prevent edge tripping/catching of advancing/retracting        elements. (4) Can facilitate a resting place for the valve        proximal end.    -   Distal valve retainer: (1) Holds and controls distal valve ring        and portion of connecting struts. (2) Prevents axial movement of        the valve until unsheathed for final release. (3) Geometry of        retainer conforms to specific valve frame geometry, providing        relief where needed. (4) Tapered ends to prevent edge        tripping/catching of advancing/retracting elements. (5) Prevents        valve jump during final release as deployment sequence        commences.    -   Proximal and/or distal retainers can include holes to facilitate        passage of recollapsing elements. The elements are attached to        the proximal or distal portions of the valve (or both) and are        used to recollapse the valve for repositioning or retrieval.    -   The proximal and distal sheath interface can be designed to seal        and interlock.    -   Although not depicted, the delivery system can incorporate a        feature that can extend outside the shaft at the distal end to        force open the calcified native leaflets prior to valve        deployment and release.    -   Various design variations are possible but only a few are        included for illustration. See, for example, the alternate        design where the proximal sheath fully encapsulates the distal        sheath. This provides protection to the distal sheath, and at        the same time provides two sheath ID sizes with further design        variations. This allows the valve proximal end to have a        collapsed diameter slightly larger than the distal end, which        provides more room and thus less leaflet tissue compression. A        possible additional benefit of the distal sheath inside the        proximal sheath is smoother system withdrawal during an        antegrade approach such as a transapical approach. Once the        valve is released from the system, the proximal sheath can be        advanced forward until it is past the leaflets. The delivery        system distal sheath can then be retracted inside the proximal        sheath and the entire system can be removed going back through        the valve. Note that during withdrawal, the leaflets will only        encounter a smooth, continuous, tube surface, as compared to a        scenario involving trying to pull the distal sheath through the        leaflets and inside of the proximal sheath before removing the        entire system.

It will be understood that the foregoing is only illustrative of theprinciples of the invention, and that various modifications can be madeby those skilled in the art without departing from the scope and spiritof the invention. For example, many details of the shapes shown forvarious components are only examples of how those details can be formed.

1. Apparatus for delivering a collapsible and re-expandable prostheticheart valve to an implant site in a patient comprising: a valve supportstructure around which the valve is disposed in a collapsed condition; asheath structure surrounding the valve on the valve support structure;and means for moving the sheath structure relative to the valve supportstructure to uncover the valve for expansion at the implant site, thevalve having first and second surface portions that face in respectiveopposite first and second directions along an axis around which thevalve is disposed on the valve support structure, and the valve supportstructure having third and fourth surface portions that respectivelyface in the second and first directions, the first and third surfaceportions being positioned adjacent to and facing one another, and thesecond and fourth surface portions being positioned adjacent to andfacing one another to substantially prevent relative movement of thevalve and the valve support structure along said axis while the valve isdisposed around the valve support structure in the collapsed condition.2. The apparatus defined in claim 1 wherein the sheath structureincludes a first sheath part that covers a first axial end part of thevalve in the collapsed condition, and a second sheath part that covers asecond axial end part of the valve in the collapsed condition.
 3. Theapparatus defined in claim 2 wherein the means for moving makes possiblemovement of one of the sheath parts relative to the other sheath part.4. The apparatus defined in claim 3 wherein the means for movingcomprises: first means for moving the first sheath part in a firstdirection that is away from the second axial end part of the valve; andsecond means for moving the second sheath part in a second directionthat is away from the first axial end part of the valve.
 5. Theapparatus defined in claim 2 wherein the first and second sheath partspartly overlap one another.
 6. The apparatus defined in claim 1 whereinthe valve support structure engages the valve in the collapsed conditionto substantially prevent the valve from rotating about the valve supportstructure.
 7. The apparatus defined in claim 1 further comprising: meansfor drawing a portion of the valve that has been uncovered by the sheathstructure radially inwardly toward the valve support structure.
 8. Theapparatus defined in claim 1 wherein the means for moving additionallyallows the sheath structure to be again moved relative to the valvesupport structure after expansion of the valve so that the sheathstructure covers the valve support structure.
 9. The apparatus definedin claim 1 wherein the valve support structure defines a passageway thatextends from a first location that is proximal of the valve to a secondlocation that is distal of the valve, with the first location beingcloser to an operator of the apparatus than the second location.
 10. Theapparatus defined in claim 1 wherein the valve support structure definesa passageway for fluid communication from a location that is proximal ofthe valve to the valve, with said location being closer to an operatorof the apparatus than the valve.
 11. The apparatus defined in claim 2wherein one of the axial end parts of the valve includes valve leaflets,and wherein the other axial end part of the valve includes valve framestructure without leaflets.
 12. The apparatus defined in claim 1 furthercomprising: a distal tip structure secured to a portion of the sheathstructure that is most distant from an operator of the apparatus, thedistal tip structure having a vent from inside the sheath structure tooutside the apparatus for facilitating de-airing of an interior of thesheath structure.
 13. The apparatus defined in claim 1 furthercomprising: a distal tip structure secured to a portion of the sheathstructure that is most distant from an operator of the apparatus; and ashaft for allowing the distal tip structure and said portion of thesheath structure to be moved distally away from the valve support,wherein the shaft includes an articulation proximal to said portion ofthe sheath structure.
 14. Apparatus for delivering a collapsible andre-expandable prosthetic heart valve to an implant site in a patientcomprising: a valve support structure around which the valve is disposedin a collapsed condition, the valve support structure having axiallyspaced proximal and distal portions, with the proximal portion beingcloser than the distal portion to an operator of the apparatus; a sheathstructure surrounding the valve on the valve support structure; andmeans for moving the sheath structure in a distal direction relative tothe valve support structure to completely uncover the valve forexpansion at the implant site.
 15. The apparatus defined in claim 14further comprising: a second sheath structure surrounding the sheathstructure; and second means for moving the second sheath structure in aproximal direction relative to the valve support structure to uncoverthe sheath structure.
 16. The apparatus defined in claim 14 wherein thevalve support structure includes elements that extend radially outwardlyinto a tubular geometric shape in which a frame structure of thecollapsed valve is disposed, said elements being positioned to interferewith motion of the valve, parallel to a longitudinal axis of the tubulargeometric shape, relative to the valve support structure.
 17. Theapparatus defined in claim 14 wherein the means for moving comprises anarticulation proximal of the sheath structure but distal of the valvesupport structure when the means for moving has moved the sheathstructure to completely uncover the valve.
 18. The apparatus defined inclaim 14 further comprising: a distal tip structure secured to a distalend of the sheath structure, the distal tip structure defining a ventfrom inside the sheath structure to outside of the apparatus.
 19. Amethod of operating apparatus for delivering a collapsible andre-expandable prosthetic heart valve to an implant site in a patientcomprising: introducing the apparatus into the patient in a distaldirection along a pathway in the patient, with the valve being disposedin a collapsed condition around a valve support structure of theapparatus, and with a sheath structure of the apparatus surrounding thevalve; and moving the sheath structure in the distal direction relativeto the valve support structure to completely uncover the valve forexpansion at the implant site.
 20. The method defined in claim 19further comprising: moving the sheath structure relative to the valvesupport structure after expansion of the valve so that the sheathstructure covers the valve support structure; and withdrawing theapparatus from the patient.
 21. The method defined in claim 19 whereinthe valve is at a first location in the apparatus that is remote from anoperator of the apparatus, and wherein the moving moves the sheathstructure to a second location that is more remote from the operatorthan the first location.
 22. The method defined in claim 21 whereinduring the introducing the sheath structure is covered by a secondsheath structure, and wherein the method further comprises: prior to themoving, moving the second sheath structure to a third location that iscloser to the operator than the first location.
 23. The method definedin claim 19 further comprising: passing additional instrumentationthrough the valve support structure to a location in the patient that ismore remote from an operator of the apparatus than the valve supportstructure.
 24. The method defined in claim 19 further comprising:passing fluid through a portion of the valve support structure from alocation, which is closer to an operator of the apparatus than the valvesupport structure, to the valve.
 25. The method defined in claim 19further comprising: drawing a portion of the valve radially inwardlytoward the valve support structure after the moving has uncovered thatportion of the valve.